Lithium-ion Battery - Patent 7858236

BACKGROUNDThe present invention relates generally to the field of lithium batteries. Specifically, the present invention relates to lithium-ion batteries that are relatively tolerant to over-discharge conditions.Lithium-ion batteries include a positive current collector (e.g., aluminum such as an aluminum foil) having an active material provided thereon (e.g., LiCoO.sub.2) and a negative current collector (e.g., copper such as a copper foil) having anactive material (e.g., a carbonaceous material such as graphite) provided thereon. Together the positive current collector and the active material provided thereon are referred to as a positive electrode, while the negative current collector and theactive material provided thereon are referred to as a negative electrode.FIG. 1 shows a schematic representation of a portion of a lithium-ion battery 10 such as that described above. The battery 10 includes a positive electrode 20 that includes a positive current collector 22 and a positive active material 24, anegative electrode 30 that includes a negative current collector 32 and a negative active material 34, an electrolyte material 40, and a separator (e.g., a polymeric microporous separator, not shown) provided intermediate or between the positiveelectrode 20 and the negative electrode 30. The electrodes 20, 30 may be provided as relatively flat or planar plates or may be wrapped or wound in a spiral or other configuration (e.g., an oval configuration). The electrode may also be provided in afolded configuration.During charging and discharging of the battery 10, lithium ions move between the positive electrode 20 and the negative electrode 30. For example, when the battery 10 is discharged, lithium ions flow from the negative electrode 30 to the to thepositive electrode 20. In contrast, when the battery 10 is charged, lithium ions flow from the positive electrode 20 to the negative electrode 30.FIG. 2 is a graph 100 illustrating the theoretical charging and disch

United States Patent: 7858236
&nbsp;
( 1 of 1 )
United States Patent
7,858,236
Howard
, &nbsp; et al.
December 28, 2010
Lithium-ion battery
Abstract
A lithium-ion battery includes a positive electrode that includes a
positive current collector, a first active material, and a second active
material. The lithium-ion battery also includes a negative electrode
comprising a negative current collector, a third active material, and a
quantity of lithium in electrical contact with the negative current
collector. The first active material, second active material, and third
active materials are configured to allow doping and undoping of lithium
ions, and the second active material exhibits charging and discharging
capacity below a corrosion potential of the negative current collector
and above a decomposition potential of the first active material.
Inventors:
Howard; William G. (Roseville, MN), Schmidt; Craig L. (Eagan, MN), Scott; Erik R. (Maple Grove, MN)
Assignee:
Medtronic, Inc.
(Minneapolis,
MN)
Appl. No.:
12/510,857
Filed:
July 28, 2009
Related U.S. Patent Documents
Application NumberFiling DatePatent NumberIssue Date
10979041Sep., 20097582387
Current U.S. Class:
429/231.3 ; 429/231.1; 429/231.5; 429/231.8; 429/231.95; 429/233; 429/245
Current International Class:
H01M 4/48&nbsp(20100101)
Field of Search:
429/231.1,231.3,231.95,231.5,233,245,218.1,231.8
References Cited [Referenced By]
U.S. Patent Documents
3462303
August 1969
Reber
3791867
February 1974
Broadhead et al.
3864167
February 1975
Broadhead et al.
3898096
August 1975
Heredy et al.
4009052
February 1977
Whittingham
4048397
September 1977
Rothbauer
4049887
September 1977
Whittingham
4113921
September 1978
Goldstein et al.
4194062
March 1980
Carides et al.
4202702
May 1980
Nuss
4340652
July 1982
Raistrick et al.
4446212
May 1984
Kaun
4464447
August 1984
Lazzari et al.
4507371
March 1985
Thackeray et al.
4547442
October 1985
Besenhard et al.
4555456
November 1985
Kanehori et al.
4668595
May 1987
Yoshino et al.
4764437
August 1988
Kaun
4830939
May 1989
Lee et al.
H723
January 1990
Plichta et al.
5053297
October 1991
Yamahira et al.
5077151
December 1991
Yasuda et al.
5147737
September 1992
Post et al.
5147739
September 1992
Beard
5160712
November 1992
Thackeray et al.
5162170
November 1992
Miyabayashi et al.
5169736
December 1992
Bittihn et al.
5176969
January 1993
Miyabayashi et al.
5187033
February 1993
Koshiba
5187035
February 1993
Miyabayashi et al.
5196279
March 1993
Tarascon
5264201
November 1993
Dahn et al.
5284721
February 1994
Beard
5296318
March 1994
Gozdz et al.
5300373
April 1994
Shackle
5322746
June 1994
Wainwright
5340666
August 1994
Tomantschger et al.
5401598
March 1995
Miyabayashi et al.
5411537
May 1995
Munshi et al.
5418090
May 1995
Koksbang et al.
5498489
March 1996
Dasgupta et al.
5510212
April 1996
Delnick et al.
5525441
June 1996
Reddy et al.
5545468
August 1996
Koshiba et al.
5547785
August 1996
Yumiba et al.
5569553
October 1996
Smesko et al.
5576608
November 1996
Nagai et al.
5652072
July 1997
Lamanna
5670862
September 1997
Lewyn
5691081
November 1997
Krause et al.
5744258
April 1998
Bai et al.
5744264
April 1998
Barker
5776628
July 1998
Kraft et al.
5882218
March 1999
Reimers
5888665
March 1999
Bugga et al.
5891592
April 1999
Mao et al.
5911947
June 1999
Mitchell
5935724
August 1999
Spillman et al.
5935728
August 1999
Spillman et al.
5968681
October 1999
Mirura et al.
6001139
December 1999
Asanuma et al.
6001507
December 1999
Ono et al.
6007947
December 1999
Mayer
6022643
February 2000
Lee et al.
6025093
February 2000
Herr
6060186
May 2000
Broussely
6067474
May 2000
Schulman et al.
6120938
September 2000
Atsumi et al.
6139518
October 2000
Mozsary et al.
6165638
December 2000
Spillman et al.
6165646
December 2000
Takada et al.
6171729
January 2001
Gan et al.
6203947
March 2001
Peled et al.
6203994
March 2001
Epps et al.
6207327
March 2001
Takada et al.
6221531
April 2001
Vaughey et al.
6228536
May 2001
Wasynczuk
6258473
July 2001
Spillman et al.
6265100
July 2001
Saaski et al.
6274271
August 2001
Koshiba et al.
6287721
September 2001
Xie et al.
6316145
November 2001
Kida et al.
6335115
January 2002
Meissner
6352798
March 2002
Lee et al.
6365301
April 2002
Michot et al.
6372384
April 2002
Fujimoto et al.
6379842
April 2002
Mayer
6451480
September 2002
Gustafson et al.
6453198
September 2002
Torgerson et al.
6461751
October 2002
Boehm et al.
6461757
October 2002
Sasayama et al.
6475673
November 2002
Yamawaki et al.
6489062
December 2002
Watanabe
6503662
January 2003
Hamamoto et al.
6528208
March 2003
Thackeray et al.
6553263
April 2003
Meadows et al.
6596439
July 2003
Tsukamoto et al.
6645670
November 2003
Gan
6645675
November 2003
Munshi
6673493
January 2004
Gan et al.
6677083
January 2004
Suzuki et al.
6706445
March 2004
Barker et al.
6720112
April 2004
Barker et al.
6730437
May 2004
Leising et al.
6737191
May 2004
Gan et al.
6759168
July 2004
Yamasaki et al.
6761744
July 2004
Tsukamoto et al.
6777132
August 2004
Barker et al.
6824920
November 2004
Iwamoto et al.
6841304
January 2005
Michot et al.
6849360
February 2005
Marple
6905795
June 2005
Jung et al.
6905796
June 2005
Ishida et al.
6908711
June 2005
Fauteux et al.
6942949
September 2005
Besenhard et al.
7029793
April 2006
Nakagawa et al.
7101642
September 2006
Tsukamoto et al.
7157185
January 2007
Marple
7177691
February 2007
Meadows et al.
7184836
February 2007
Meadows et al.
7191008
March 2007
Schmidt et al.
7211350
May 2007
Amatucci
7337010
February 2008
Howard et al.
7459235
December 2008
Choi et al.
7524580
April 2009
Birke et al.
7541114
June 2009
Ohzuku et al.
7563541
July 2009
Howard et al.
7582380
September 2009
Dunstan et al.
7582387
September 2009
Howard et al.
7818068
October 2010
Meadows et al.
2001/0008725
July 2001
Howard
2001/0012590
August 2001
Ehrlich
2001/0021472
September 2001
Barker et al.
2001/0031401
October 2001
Yamawaki et al.
2003/0025482
February 2003
Tsukamoto et al.
2003/0104282
June 2003
Xing et al.
2003/0124423
July 2003
Sasaki et al.
2003/0157410
August 2003
Jarvis et al.
2003/0215716
November 2003
Suzuki et al.
2004/0023117
February 2004
Imachi et al.
2004/0062989
April 2004
Ueno et al.
2004/0072072
April 2004
Suzuki et al.
2004/0096745
May 2004
Shibano et al.
2004/0147971
July 2004
Greatbatch et al.
2004/0147972
July 2004
Greatbatch et al.
2004/0158296
August 2004
Greatbatch et al.
2004/0168307
September 2004
Hong
2004/0176818
September 2004
Wahlstrand et al.
2004/0197657
October 2004
Spitler et al.
2004/0209156
October 2004
Ren et al.
2005/0031919
February 2005
Ovshinsky et al.
2005/0069777
March 2005
Takami et al.
2005/0130043
June 2005
Gao et al.
2005/0147889
July 2005
Ohzuku et al.
2005/0164082
July 2005
Kishi et al.
2005/0244716
November 2005
Ogawa et al.
2006/0024582
February 2006
Li et al.
2006/0046149
March 2006
Yong et al.
2006/0068282
March 2006
Kishi et al.
2006/0093871
May 2006
Howard et al.
2006/0093872
May 2006
Howard et al.
2006/0093873
May 2006
Howard et al.
2006/0093894
May 2006
Scott et al.
2006/0093913
May 2006
Howard et al.
2006/0093917
May 2006
Howard et al.
2006/0093921
May 2006
Scott et al.
2006/0093923
May 2006
Howard et al.
2006/0216612
September 2006
Jambunathan et al.
2006/0234125
October 2006
Valle
2006/0251968
November 2006
Tsukamoto et al.
2007/0009801
January 2007
Inagaki et al.
2007/0059587
March 2007
Kishi et al.
2007/0072085
March 2007
Chen et al.
2007/0077496
April 2007
Scott et al.
2007/0111099
May 2007
Nanjundaswamy et al.
2007/0134556
June 2007
Sano et al.
2007/0162083
July 2007
Schmidt et al.
2007/0233195
October 2007
Wahlstrand et al.
2007/0239221
October 2007
Kast et al.
2007/0248881
October 2007
Scott et al.
2007/0284159
December 2007
Takami et al.
2008/0020278
January 2008
Schmidt et al.
2008/0020279
January 2008
Schmidt et al.
2008/0026297
January 2008
Chen et al.
2008/0044728
February 2008
Schmidt et al.
2009/0035662
February 2009
Scott et al.
2009/0208845
August 2009
Howard et al.
2009/0274849
November 2009
Scott et al.
Foreign Patent Documents
0 567 149
Apr., 1992
EP
0 732 761
Mar., 1996
EP
0 982 790
Mar., 1998
EP
1 018 773
Apr., 1999
EP
1 014 465
Dec., 1999
EP
1 069 635
May., 2000
EP
1 282 180
Jul., 2001
EP
1 487 039
Dec., 2004
EP
1 722 439
Nov., 2006
EP
56-136462
Oct., 1981
JP
57-011476
Jan., 1982
JP
63-1708
Jan., 1982
JP
57-152669
Sep., 1982
JP
02-309568
Dec., 1990
JP
6-275263
Sep., 1994
JP
10-027626
Jan., 1998
JP
2000-156229
Jun., 2000
JP
2000-195499
Jul., 2000
JP
2001-126756
May., 2001
JP
2001-185141
Jul., 2001
JP
WO 97/06569
Feb., 1997
WO
WO 97/48141
Dec., 1997
WO
WO 00/17950
Mar., 2000
WO
WO 01/33656
May., 2001
WO
WO 02/09215
Jan., 2002
WO
WO 02/21628
Mar., 2002
WO
WO 02/39524
May., 2002
WO
WO 02/069414
Sep., 2002
WO
WO 02/095845
Nov., 2002
WO
WO 03/044880
May., 2003
WO
WO 03/075371
Sep., 2003
WO
WO 03/075376
Sep., 2003
WO
WO 03/090293
Oct., 2003
WO
WO 2006/050022
May., 2006
WO
WO 2006/050023
May., 2006
WO
WO 2006/050098
May., 2006
WO
WO 2006/050099
May., 2006
WO
WO 2006/050100
May., 2006
WO
WO 2006/050117
May., 2006
WO
WO 2006/064344
Jun., 2006
WO
Other References
US. Appl. No. 12/567,415, filed Sep. 25, 2009, Howard et al. cited by other
.
U.S. Appl. No. 12/564,818, filed Sep. 22, 2009, Howard et al. cited by other
.
U.S. Appl. No. 12/511,942, filed Jul. 29, 2009, Howard et al. cited by other
.
U.S. Appl. No. 12/454,718, filed May 21, 2009, Scott et al. cited by other
.
U.S. Appl. No. 12/433,557, filed Apr. 30, 2009, Scott et al. cited by other
.
"Battery Materials--Ceramic Anode Material for 2.4 V Lithium-Ion Batteries"--EXM 1037--Li.sub.4Ti.sub.5O.sub.12 (1 page), available at least by Oct. 25, 2004. cited by other
.
Ariyoshi, et al., "Three-Volt Lithium-Ion Battery with Li[Ni.sub.1/2Mn.sub. 3/2]O.sub.4 and the Zero-Strain Insertion Material of Li[Li.sub.1/3Ti.sub. 5/3]O.sub.4", Journal of Power Sources, 119-121, 2003, pp. 959-963. cited by other
.
Belharouak et al., "On the Safety of the Li.sub.4Ti.sub.5O.sub.12/LiMn.sub.2O.sub.4 Lithium-Ion Battery System," (ECS) Journal of the Electrochemical Society, 2007, pp. A1083-A1087, vol. 154, No. 12. cited by other
.
Brohan et al., Properties Physiques Des Bronzes M.sub.xTiO.sub.2(B), Solid State Ionics, vols. 9 and 10, 1983, .COPYRGT. North Holland Publishing Company, pp. 419-424. cited by other
.
Cava et al., The Crystal Structures of the Lithium-Inserted Metal Oxides Li.sub.0.5TiO.sub.2 Anatase, LiTi.sub.2O.sub.4 Spinel, and Li.sub.2Ti.sub.2O.sub.4, Journal of Solid State Chemistry, vol. 53, Jan. 1984 .COPYRGT. Academic Press, Inc., pp.
64-75. cited by other
.
Christensen et al., "Optimization of Lithium Titanate Electrodes for High-Power Cells," (ECS) Journal of the Electrochemical Society, 2006, pp. A560-A565, vol. 153, No. 3. cited by other
.
Colbow et al., Structure and Electrochemistry of the Spinel Oxides LiTi.sub.2O.sub.4 and Li.sub. 4/3Ti.sub. 5/3O.sub.4, Journal of Power Sources, vol. 26, 1989, .COPYRGT. Elsevier Sequoia, pp. 397-402. cited by other
.
Dahn et al., "Combinatorial Study of Sn1-xCox (0&lt;x&lt;0.6) and [Sn0.55Co0.45]1-yCy (0&lt;y&lt;0.5) Alloy Negative Electrode Materials for Li-Ion Batteries," Journal of Electrochemical Society, vol. 153, 2006, pp. A361-365. cited by other
.
Fauteux et al., "Rechargeable lithium battery anodes: alternatives to metallic lithium," Journal of Applied Electrochemistry, vol. 23, 1993, pp. 1-10. cited by other
.
Ferg et al, "Spinel Anodes for Lithium-Ion Batteries", J. Electrochem. Soc. vol. 141 #11, 1994, pp. L147-L150. cited by other
.
FMC Lithium, CAS No. 74389-93-2, "Stabilized Lithium Metal Powder" Product Specification, Copyright 2001 FMC Corporation (2 pages). cited by other
.
Guerfi, et. al., "Nano Electronically Conductive Titanium-Spinel as Lithium Ion Storage Negative Electrode", Journal of Power Sources, 126, 2004, pp. 163-168. cited by other
.
Guyomard et al., "New amorphous oxides as high capacity negative electrodes for lithium6 batteries the LixMV04 (M=Ni, Co, Cd, Zn; 1 &lt;x&lt;8) series," Journal of Power Sources, vol. 68, 1997, pp. 692-697. cited by other
.
Jansen, et. al., "Development of A High-Power Lithium-Ion Battery", Journal of Power Sources, 81-82, 1999, pp. 902-905. cited by other
.
Jarvis et al., "A Li-Ion Cell Containing a Non-Lithiated Cathode", Abs. 182, IMLB 12 Meeting (1 page). cited by other
.
Kavan, et al., Proof of Concept--Li.sub.4Ti.sub.5O.sub.12, Electrochemical and Solid State Letters, 2002, vol. 5, A39-A42, p. 13. cited by other
.
Linden, David, Editor in Chief, Handbook of Batteries, Second Edition, McGraw-Hill, NY, 1995, 6 pages. cited by other
.
Mikula et al., Photoelectrochemical Properties of Anodic TiO.sub.2 Layers Prepared by Various Current Densities, J. Electrochemical Society, vol. 139, No. 12, Dec. 1992 .COPYRGT. The Electrochemical Society, Inc., pp. 3470-3474. cited by other
.
Murphy et al., "Topochemical Reactions of Rutile Related Structures with Lithium", Mat. Res. Bull, vol. 13, No. 12, 1978, .COPYRGT. Pergamon Press, Inc., pp. 1395-1402. cited by other
.
Murphy et al., Lithium Insertion in Anatase: A New Route to the Spinel LiTi.sub.2O.sub.4, Revue De Chimie Minerale, vol. 19, 1982, 9 pgs. cited by other
.
Murphy et al., Ternary Li.sub.xTiO.sub.2 Phases from Insertion Reactions, Solid State Ionics, vols. 9 & 10, 1983 .COPYRGT. North-Holland Publishing Company, pp. 413-418. cited by other
.
Nakahara, et al. "Preparation of Particulate Li.sub.4Ti.sub.5O.sub.12 Having Excellent Characteristics As An Electrode Active Material for Power Storage Cells", Journal of Power Sources, 117, 2003, pp. 131-136. cited by other
.
New Li.sub.4Ti.sub.5O.sub.12 Anode Material of Sud-Chemie AG for Lithium Ion Batteries, Sud-Chemie EXM 1037--Li.sub.4Ti.sub.5O.sub.12, Product Specification (2 pages). cited by other
.
Ohzuku et al., "Why transition metal (di)oxides are the most attractive materials for batteries," Solid State Ionics, vol. 69, 1994, pp. 201-211. cited by other
.
Ohzuku et al., "Lithium-Ion Batteries of Li[Li.sub.1/3Ti.sub. 5/3]O.sub.4 With Selected Positive-Electrode Materials for Long-Life Power Application", Abs. 23, IMLB 12 Meeting (1 page). cited by other
.
Ohzuku et al., Zero-Strain Insertion Material of Li[Li.sub.1/3Ti.sub. 5/3]O.sub.4 for Rechargeable Lithium Cells, Electrochemical Science and Technology, J. Electrochem Soc., vol. 142, No. 5, May 1995 .COPYRGT. The Electrochemical Society, Inc., 5
pages. cited by other
.
Ohzuku, Extended Abstracts from the Seventh Int'l Meeting on Li Batteries, Boston, MA, May 15-20, 1994, pp. 111-112. cited by other
.
Peramunage et al., Preparation of Micro-Sized Li.sub.4Ti.sub.5O.sub.12 and Its Electrochemistry in Polyacrylonitrile Electrolye-Based Lithium Cells, Technical Papers, Electrochemical Science and Technology, J. Electrochem Soc., vol. 145, No. 8, Aug.
1998 .COPYRGT. The Electrochemical Society, Inc., 7 pages. cited by other
.
Poizot et al., "Nano-sized transition-metal oxides as negative-electrode materials for lithium-ion batteries," Nature, vol. 407, 2000, cover and pp. 496-499. cited by other
.
Prosini, et. al., "Li.sub.4Ti.sub.5O.sub.12 As Anode in All-Solid-State, Plastic, Lithium-Ion Batteries for Low-Power Applications" Solid State Ionics, 144, 2001, pp. 185-192. cited by other
.
Sasaki et al., Layered Hydrous Titanium Dioxide: Potassium Ion Exchange and Structural Characterization, Inorganic Chemistry, vol. 24, No. 14, .COPYRGT. 1985 American Chemical Society, pp. 2265-2271. cited by other
.
Sawai, et al., Factors Affecting Rate Capability of a Lithium-ion Battery with Li[Li.sub.1/3Ti.sub. 5/3]0.sub.4 and LiCo.sub.1/2Ni.sub.1/20.sub.2, Abs. 75, 205.sup.th Meeting, 1 page. cited by other
.
Scrosati, "Low Voltage Lithium-Ion Cells", Advances in Lithium-Ion Batteries Kluwer Academic/Plenum Publishers, pp. 289-308. cited by other
.
Singhal, et al. "Nanostructured Electrodes for Next Generation Rechargeable Electrochemical Devices", Journal of Power Sources, 129, 2004, pp. 38-44. cited by other
.
Sun et al., "The Compatibility of a Boron-Based Anion Receptor with the Carbon Anode in Lithium-Ion Batteries," (ECS) Electrochemical and Solid-State Letters, 2003, pp. A43-A46, vol. 6, No. 2. cited by other
.
Sun et al., "Using a Boron-Based Anion Receptor Additive to Improve the Thermal Stability of LiPF.sub.6-Based Electrolyte for Lithium Batteries," (ECS) Electrochemical and Solid-State Letters, 2002, pp. A248-A251, vol. 5, No. 11. cited by other
.
Trifonova et al., "Sn-Sb and Sn-Bi Alloys as Anode Materials for Lithium-Ion Batteries," Ionics, vol. 8, 2002, cover and pages 321-328. cited by other
.
Wang et al., Li Insertion and Ion Exchange Reactions in the Ionic Conducting TI2(M,Ti)8O16 Phases with Hollandite-Type Structure, Technical Papers, Solid-State Science and Technology, J. Electrochem Soc., vol. 138, No. 1, Jan. 1991, .COPYRGT. The
Electrochemical Society, Inc., pp. 166-172. cited by other
.
Wang et al., Novel Eletrolytes for Nanocrystalline Li.sub.4Ti.sub.5O.sub.12 Based High Power Lithium Ion Batteries, 1 page. cited by other
.
Winter et al., "Insertion Electrode Materials for Rechargeable Lithium Batteries," Advanced Materials, vol. 10, 1998, pp. 725-763. cited by other
.
Winter et al., "Electrochemical lithiation of tin and tin-based intermetallics and composites," Electrochimica Acta, vol. 45, 1999, pp. 31-50. cited by other
.
Zaghib, et al, "Electrochemical Study of Li.sub.4Ti.sub.5O.sub.12 As Negative Electrode for Li-Ion Polymer Rechargeable Batteries", Journal of Power Sources, 81-82, 1999, pp. 300-305. cited by other
.
International Search Report for PCT/US2005/038761, date of mailing Oct. 4, 2006, 2 pages. cited by other
.
International Search Report for PCT/US2005/038762, date of mailing Oct. 2, 2006, 2 pages. cited by other
.
International Search Report for PCT/US2005/038942, date of mailing, Mar. 2, 2006, 3 pages. cited by other
.
International Search Report for PCT/US2005/038943, date of mailing, Mar. 16, 2006, 3 pages. cited by other
.
International Search Report for PCT/US2005/038944, date of mailing, Mar. 31, 2006, 3 pages. cited by other
.
International Search Report for PCT/US2005/038970, date of mailing Oct. 25, 2006, 3 pages. cited by other
.
International Search Report and Written Opinion for Application No. PCT/US2008/066809, mailing date Oct. 29, 2008, 8 pages. cited by other
.
International Search Report and Written Opinion for Application No. PCT/US2008/066801, mailing date Oct. 29, 2008, 10 pages. cited by other
.
International Search Report and Written Opinion for Application No. PCT/US2008/066803, date of mailing Oct. 7, 2008, 12 pages. cited by other
.
International Search Report and Written Opinion for Application No. PCT/US2008/082598, date of mailing Feb. 18, 2009, 11 pages. cited by other
.
Restriction Requirement for U.S. Appl. No. 10/979,041, dated Jan. 30, 2008, 8 pages. cited by other
.
Reply and Amendment for U.S. Appl. No. 10/979,041, filed Feb. 22, 2008, 6 pages. cited by other
.
Non-Final Office Action for U.S. Appl. No. 10/979,041, dated Apr. 4, 2008, 13 pages. cited by other
.
Reply and Amendment and Declaration Under 1.131 for U.S. Appl. No. 10/979,041, filed Aug. 4, 2008, 64 pages. cited by other
.
Non-Final Office Action for U.S. Appl. No. 10/979,041, dated Oct. 20, 2008, 11 pages. cited by other
.
Amendment and Reply for U.S. Appl. No. 10/979,041, filed Mar. 6, 2009, 19 pages. cited by other
.
Terminal Disclaimer for U.S. Appl. No. 10/979,041, filed Apr. 21, 2009, 3 pages. cited by other
.
Notice of Allowance for U.S. Appl. No. 10/979,041, dated Apr. 30, 2009, 7 pages. cited by other
.
Non-Final Office Action for U.S. Appl. No. 10/978,681, dated Mar. 18, 2008, 6 pages. cited by other
.
Amendment and Reply, Drawings and Terminal Disclaimer for U.S. Appl. No. 10/978,681, filed May 28, 2008, 19 pages. cited by other
.
Notice of Allowance for U.S. Appl. No. 10/978,681, dated Jul. 16, 2008, 8 pages. cited by other
.
Request for Continued Examination (RCE) for U.S. Appl. No. 10/978,681, filed Oct. 2, 2008, 4 pages. cited by other
.
Notice of Allowance for U.S. Appl. No. 10/978,681, dated Oct. 24, 2008, 8 pages. cited by other
.
Notice of Withdrawal from Issue for U.S. Appl. No. 10/978,681, dated Nov. 26, 2008, 2 pages. cited by other
.
Non-Final Office Action for U.S. Appl. No. 10/978,681, dated Dec. 9, 2008, 13 pages. cited by other
.
Amendment and Reply for U.S. Appl. No. 10/978,681, filed Mar. 6, 2009, 20 pages. cited by other
.
Non-Final Office Action for U.S. Appl. No. 10/978,681, dated May 22, 2009, 7 pages. cited by other
.
Amendment and Reply and Terminal Disclaimer for U.S. Appl. No. 10/978,681, filed Jul. 20, 2009, 16 pages. cited by other
.
Notice of Allowance for U.S. Appl. No. 10/978,681, dated Sep. 22, 2009, 7 pages. cited by other
.
U.S. Appl. No. 12/789,149, filed May 27, 2010, Howard et al. cited by other
.
Non-Final Office Action for U.S. Appl. No. 10/979,043, dated Apr. 2, 2008, 14 pages. cited by other
.
Amendment and Reply and Declaration Under 1.131 for U.S. Appl. No. 10/979,043, filed Aug. 4, 2008, 60 pages. cited by other
.
Non-Final Office Action for U.S. Appl. No. 10/979,043, dated Oct. 21, 2008, 9 pages. cited by other
.
Amendment and Reply for U.S. Appl. No. 10/979,043, filed Jan. 8, 2009, 17 pages. cited by other
.
Non-Final Office Action for U.S. Appl. No. 10/979,043, dated Feb. 26, 2009, 9 pages. cited by other
.
Amendment and Reply for U.S. Appl. No. 10/979,043, filed May 19, 2009, 16 pages. cited by other
.
Final Office Action for U.S. Appl. No. 10/979,043, dated Jul. 29, 2009, 10 pages. cited by other
.
Amendment and Reply and Terminal Disclaimer for U.S. Appl. No. 10/979,043, filed Oct. 26, 2009, 18 pages. cited by other
.
Advisory Action for U.S. Appl. No. 10/979,043, dated Nov. 12, 2009, 3 pages. cited by other
.
Request for Continued Examination (RCE) and Amendment and Reply for U.S. Appl. No. 10/979,043, filed Nov. 25, 2009, 15 pages. cited by other
.
Notice of Allowance for U.S. Appl. No. 10/979,043, dated Dec. 28, 2009, 14 pages. cited by other
.
Amendment Under 1.312 for U.S. Appl. No. 10/979,043, filed Mar. 5, 2010, 10 pages. cited by other
.
Response to Amendment Under 1.312 for U.S. Appl. No. 10/979,043, dated Mar. 10, 2010, 2 pages. cited by other
.
Petition for Withdrawal from Issue and Request for Continued Examination (RCE) for U.S. Appl. No. 10/979,043, filed Jun. 4, 2010, 6 pages. cited by other
.
Notice of Allowance for U.S. Appl. No. 10/979,043, dated Jun. 16, 2010, 8 pages. cited by other.
Primary Examiner: Weiner; Laura S
Attorney, Agent or Firm: Marks; Scott A.
Foley & Lardner LLP
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a Divisional of U.S. patent application Ser.
No. 10/979,041 filed Oct. 29, 2004, which issued on Sep. 1, 2009 as U.S.
Pat. No. 7,582,387, the entire disclosure of which is incorporated herein
by reference.
Claims
What is claimed is:
1. A lithium-ion battery comprising: a positive electrode comprising a positive current collector having a primary active material and a secondary active material provided on
at least one side thereof; a negative electrode comprising a negative current collector and an active material provided on the negative current collector; wherein the primary active material is LiCoO.sub.2, wherein the secondary active material does
not include lithium, wherein the secondary active material is selected from the group consisting of V.sub.6O.sub.13, V.sub.2O.sub.5, and V.sub.3O.sub.8, wherein the secondary active material provides for a charging and discharging capacity of the
positive electrode that is below a corrosion potential of the negative current collector and above a decomposition potential of the primary active material, and wherein the active material provided on the negative current collector is a carbonaceous
material.
2. The lithium-ion battery of claim 1, wherein the positive electrode and the negative electrode have a zero voltage crossing potential below the corrosion potential of the negative current collector and above the decomposition potential of the
primary active material.
3. The lithium-ion battery of claim 2, wherein the corrosion potential of the negative current collector is approximately 3.5 volts.
4. The lithium-ion battery of claim 1, further comprising a mass of lithium provided in electrical contact with the negative current collector.
5. The lithium-ion battery of claim 4, wherein the mass of lithium is configured to provide a lithium capacity for the negative electrode sufficient to at least compensate for irreversible loss of capacity of the negative electrode.
6. The lithium-ion battery of claim 5, wherein the mass of lithium is configured to provide a lithium capacity equal to the sum of the irreversible loss of capacity of the negative electrode and the capacity of the secondary active material.
7. The lithium-ion battery of claim 4, wherein the mass of lithium is provided as powdered lithium.
8. The lithium-ion battery of claim 1, wherein the negative current collector comprises copper.
9. The lithium-ion battery of claim 1, further comprising a polymeric separator provided intermediate the positive electrode and the negative electrode.
10. The lithium-ion battery of claim 1, wherein the battery has a capacity between approximately 10 mAh and 1000 mAh. Description
BACKGROUND
The present invention relates generally to the field of lithium batteries. Specifically, the present invention relates to lithium-ion batteries that are relatively tolerant to over-discharge conditions.
Lithium-ion batteries include a positive current collector (e.g., aluminum such as an aluminum foil) having an active material provided thereon (e.g., LiCoO.sub.2) and a negative current collector (e.g., copper such as a copper foil) having an
active material (e.g., a carbonaceous material such as graphite) provided thereon. Together the positive current collector and the active material provided thereon are referred to as a positive electrode, while the negative current collector and the
active material provided thereon are referred to as a negative electrode.
FIG. 1 shows a schematic representation of a portion of a lithium-ion battery 10 such as that described above. The battery 10 includes a positive electrode 20 that includes a positive current collector 22 and a positive active material 24, a
negative electrode 30 that includes a negative current collector 32 and a negative active material 34, an electrolyte material 40, and a separator (e.g., a polymeric microporous separator, not shown) provided intermediate or between the positive
electrode 20 and the negative electrode 30. The electrodes 20, 30 may be provided as relatively flat or planar plates or may be wrapped or wound in a spiral or other configuration (e.g., an oval configuration). The electrode may also be provided in a
folded configuration.
During charging and discharging of the battery 10, lithium ions move between the positive electrode 20 and the negative electrode 30. For example, when the battery 10 is discharged, lithium ions flow from the negative electrode 30 to the to the
positive electrode 20. In contrast, when the battery 10 is charged, lithium ions flow from the positive electrode 20 to the negative electrode 30.
FIG. 2 is a graph 100 illustrating the theoretical charging and discharging behavior for a conventional lithium-ion battery. Curve 110 represents the electrode potential versus a lithium reference electrode for a positive electrode that includes
an aluminum current collector having a LiCoO.sub.2 active material provided thereon, while curve 120 represents the electrode potential versus a lithium reference electrode for a negative electrode that includes a copper current collector having a
carbonaceous active material provided thereon. The difference between curves 110 and 120 is representative of the overall cell voltage.
As shown in FIG. 2, upon initial charging to full capacity, the potential of the positive electrode, as shown by curve 110, increases from approximately 3.0 volts to a point above the corrosion potential of copper used to form the negative
electrode (designated by dashed line 122). The potential of the negative electrode decreases from approximately 3.0 volts to a point below the decomposition potential of the LiCoO.sub.2 active material provided on the aluminum current collector
(designated by dashed line 112). Upon initial charging, the battery experiences an irreversible loss of capacity due to the formation of a passive layer on the negative current collector, which may be referred to as a solid-electrolyte interface
("SEI"). The irreversible loss of capacity is shown as a ledge or shelf 124 in curve 120.
One difficulty with conventional lithium-ion batteries is that when such a battery is discharged to a point near zero volts, it may exhibit a loss of deliverable capacity and corrosion of the negative electrode current collector (copper) and
possibly of the battery case, depending on the material used and the polarity of the case. As shown in FIG. 2, after initial charging of the battery, a subsequent discharge of the battery in which the voltage of the battery approaches zero volts (i.e.,
zero percent capacity) results in a negative electrode potential that follows a path designated by dashed line 126. As shown in FIG. 2, the negative electrode potential levels off or plateaus at the copper corrosion potential of the negative current
collector (approximately 3.5 volts for copper and designated by dashed line 122 in FIG. 2).
The point at which the curves 110 and 120 cross is sometimes referred to as the zero voltage crossing potential, and corresponds to a cell voltage that is equal to zero (i.e., the difference between the two curves equals zero at this point).
Because of the degradation of the copper current collector which occurs at the copper corrosion potential, the copper material used for the negative current collector corrodes before the cell reaches a zero voltage condition, resulting in a battery that
exhibits a dramatic loss of deliverable capacity.
While FIG. 2 shows the theoretical charging and discharging behavior of a battery that may experience corrosion of the negative current collector when the battery approaches a zero voltage configuration, it should be noted that there may also be
cases in which the active material on the positive current collector may degrade in near-zero-voltage conditions. In such cases, the theoretical charging and discharging potential of the positive electrode versus a lithium reference electrode would
decrease to the decomposition potential of the positive active material (shown as line 112 in FIG. 2), at which point the positive active material would decompose, resulting in potentially decreased protection against future over-discharge conditions.
Because damage to the lithium-ion battery may occur in the event of a low voltage condition, conventional lithium-ion batteries may include protection circuitry and/or may be utilized in devices that include protection circuitry which
substantially reduces the current drain from the battery (e.g., by disconnecting the battery).
The medical device industry produces a wide variety of electronic and mechanical devices for treating patient medical conditions. Depending upon the medical condition, medical devices can be surgically implanted or connected externally to the
patient receiving treatment. Clinicians use medical devices alone or in combination with drug therapies and surgery to treat patient medical conditions. For some medical conditions, medical devices provide the best, and sometimes the only, therapy to
restore an individual to a more healthful condition and a fuller life.
It may be desirable to provide a source of battery power for such medical devices, including implantable medical devices. In such cases, it may be advantageous to provide a battery that may be recharged. It may also be advantageous to provide a
battery that may be discharged to a near zero voltage condition without substantial risk that the battery may be damaged (e.g., without corroding one of the electrodes or the battery case, decomposing the positive active material, etc.) such that the
performance of the battery is degraded in subsequent charging and discharging operations.
It would be advantageous to provide a battery (e.g., a lithium-ion battery) that may be discharged to near zero volts without producing a subsequent decrease in the amount of deliverable capacity or producing a corroded negative electrode or
battery case. It would also be advantageous to provide a battery that compensates for the irreversible loss of capacity resulting from initial charging of the battery to allow the battery to be used in near zero voltage conditions without significant
degradation to battery performance. It would also be advantageous to provide a medical device (e.g., an implantable medical device) that utilizes a battery that includes any one or more of these or other advantageous features.
SUMMARY
An exemplary embodiment relates to a lithium-ion battery that includes a positive electrode that includes a positive current collector, a first active material, and a second active material. The lithium-ion battery also includes a negative
electrode comprising a negative current collector, a third active material, and a quantity of lithium in electrical contact with the negative current collector. The first active material, second active material, and third active materials are configured
to allow doping and undoping of lithium ions, and the second active material exhibits charging and discharging capacity below a corrosion potential of the negative current collector and above a decomposition potential of the first active material.
Another exemplary embodiment relates to a lithium-ion battery that includes a positive electrode comprising a current collector having a primary active material and a secondary active material provided on at least one side thereof. The
lithium-ion battery also includes a negative electrode having a negative current collector and an active material provided on the negative current collector. The secondary active material does not include lithium and provides charging and discharging
capacity for the positive electrode below a corrosion potential of the negative current collector and above a decomposition potential of the primary active material.
Another exemplary embodiment relates to a lithium-ion battery that includes a positive electrode comprising a current collector having a primary active material and a secondary active material provided on at least one side thereof. The
lithium-ion battery also includes a negative electrode having a negative current collector and an active material provided on the negative current collector. A quantity of lithium is in electrical contact with the negative current collector. The
secondary active material does not include lithium and provides charging and discharging capacity for the positive electrode below a corrosion potential of the negative current collector and above a decomposition potential of the primary active material.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic cross-sectional view of a conventional lithium-ion battery.
FIG. 2 is a graph illustrating the theoretical charging and discharging behavior for a conventional lithium-ion battery such as that shown schematically in FIG. 1.
FIG. 3 is a schematic cross-sectional view of a portion of a lithium-ion battery according to an exemplary embodiment.
FIG. 4 is a schematic cross-sectional view of a portion of a lithium-ion battery according to another exemplary embodiment.
FIG. 5 is a graph illustrating the theoretical charging and discharging behavior for a lithium-ion battery such as that shown in FIG. 3.
FIG. 6 is a schematic view of a system in the form of an implantable medical device implanted within a body or torso of a patient.
FIG. 7 is schematic view of another system in the form of an implantable medical device.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
With reference to FIG. 3, a schematic cross-sectional view of a portion of a lithium-ion battery 200 is shown according to an exemplary embodiment. According to an exemplary embodiment, the battery 200 has a rating of between approximately 10
and 1000 milliampere hours (mAh). According to another exemplary embodiment, the battery has a rating of between approximately 100 and 400 mAh. According to another exemplary embodiment, the battery is an approximately 300 mAh battery. According to
another exemplary embodiment, the battery is an approximately 75 mAh battery.
The battery 200 includes at least one positive electrode 210 and at least one negative electrode 220. The electrodes may be provided as flat or planar components of the battery 200, may be wound in a spiral or other configuration, or may be
provided in a folded configuration. For example, the electrodes may be wrapped around a relatively rectangular mandrel such that they form an oval wound coil for insertion into a relatively prismatic battery case. According to other exemplary
embodiments, the battery may be provided as a button cell battery, a thin film solid state battery, or as another lithium-ion battery configuration.
The battery case (not shown) may be made of stainless steel or another metal. According to an exemplary embodiment, the battery case may be made of titanium, aluminum, or alloys thereof. According to another exemplary embodiment, the battery
case may be made of a plastic material or a plastic-foil laminate material (e.g., an aluminum foil provided intermediate a polyolefin layer and a polyester layer).
According to an exemplary embodiment, the negative electrode is coupled to a stainless steel case by a member or tab comprising nickel or a nickel alloy. An aluminum or aluminum alloy member or tab may be coupled or attached to the positive
electrode. The nickel and aluminum tabs may serve as terminals for the battery according to an exemplary embodiment.
The dimensions of the battery 200 may differ according to a variety of exemplary embodiments. For example, according to one exemplary embodiment in which the electrodes are wound such that they may be provided in a relatively prismatic battery
case, the battery has dimensions of between approximately 30-40 mm by between approximately 20-30 mm by between approximately 5-7 mm. According to another exemplary embodiment, the dimensions of the battery are approximately 20 mm by 20 mm by 3 mm.
According to another exemplary embodiment, a battery may be provided in the form of a button cell type battery having a diameter of approximately 30 mm and a thickness of approximately 3 mm. It will be appreciated by those of skill in the art that such
dimensions and configurations as are described herein are illustrative only, and that batteries in a wide variety of sizes, shapes, and configurations may be produced in accordance with the novel concepts described herein.
An electrolyte 230 is provided intermediate or between the positive and negative electrodes to provide a medium through which lithium ions may travel. According to an exemplary embodiment, the electrolyte may be a liquid (e.g., a lithium salt
dissolved in one or more non-aqueous solvents). According to another exemplary embodiment, the electrolyte may be a lithium salt dissolved in a polymeric material such as poly(ethylene oxide) or silicone. According to another exemplary embodiment, the
electrolyte may be an ionic liquid such as N-methyl-N-alkylpyrrolidinium bis(trifluoromethanesulfonyl)imide salts. According to another exemplary embodiment, the electrolyte may be a solid state electrolyte such as a lithium-ion conducting glass such as
lithium phosphorous oxynitride (LiPON).
Various other electrolytes may be used according to other exemplary embodiments. For example, according to an exemplary embodiment, the electrolyte may be a 1:1 mixture of ethylene carbonate to diethylene carbonate (EC:DEC) in a 1.0 M salt of
LiPF.sub.6. According to another exemplary embodiment, the electrolyte may include a polypropylene carbonate solvent and a lithium bis-oxalatoborate salt (sometimes referred to as LiBOB). According to other exemplary embodiments, the electrolyte may
comprise one or more of a PVDF copolymer, a PVDF-polyimide material, and organosilicon polymer, a thermal polymerization gel, a radiation cured acrylate, a particulate with polymer gel, an inorganic gel polymer electrolyte, an inorganic gel-polymer
electrolyte, a PVDF gel, polyethylene oxide (PEO), a glass ceramic electrolyte, phosphate glasses, lithium conducting glasses, lithium conducting ceramics, and an inorganic ionic liquid or gel, among others.
A separator 250 is provided intermediate or between the positive electrode 210 and the negative electrode 220. According to an exemplary embodiment, the separator 250 is a polymeric material such as a polypropylene/polyethelene copolymer or
another polyolefin multilayer laminate that includes micropores formed therein to allow electrolyte and lithium ions to flow from one side of the separator to the other. The thickness of the separator 250 is between approximately 10 micrometers (.mu.m)
and 50 .mu.m according to an exemplary embodiment. According to a particular exemplary embodiment, the thickness of the separator is approximately 25 .mu.m and the average pore size of the separator is between approximately 0.02 .mu.m and 0.1 .mu.m.
The positive electrode 210 includes a current collector 212 made of a conductive material such as a metal. According to an exemplary embodiment, the current collector 212 comprises aluminum or an aluminum alloy. According to an exemplary
embodiment, the thickness of the current collector 212 is between approximately 5 .mu.m and 75 .mu.m. According to a particular exemplary embodiment, the thickness of the current collector 212 is approximately 20 .mu.m. It should also be noted that
while the positive current collector 212 has been illustrated and described as being a thin foil material, the positive current collector may have any of a variety of other configurations according to various exemplary embodiments. For example, the
positive current collector may be a grid such as a mesh grid, an expanded metal grid, a photochemically etched grid, or the like.
The current collector 212 has a layer of active material 214 provided thereon (e.g., coated on the current collector). While FIG. 3 shows that the layer of active material 214 is provided on only one side of the current collector 212, it should
be understood that a layer of active material similar or identical to that shown as layer 214 may be provided or coated on both sides of the current collector 212.
As shown in FIG. 3, layer 214 includes a primary active material 216 and a secondary or auxiliary active material 218. While the primary active material 216 and the secondary active material 218 are shown as being provided as separate individual
layers according to an exemplary embodiment, it will be appreciated that the primary active material 216 and the secondary active material 218 may be provided as a single active material layer in which the primary and secondary active materials are
intermixed (see, e.g., the exemplary embodiment shown in FIG. 4, in which layer 214 includes both the primary active material 216 and the secondary active material 218). A binder material may also be utilized in conjunction with the layer of active
material 214 to bond or hold the various electrode components together. For example, according to an exemplary embodiment, the layer of active material may include a conductive additive such as carbon black and a binder such as polyvinylidine fluoride
(PVDF) or an elastomeric polymer.
According to an exemplary embodiment, the primary active material 216 is a material or compound that includes lithium. The lithium included in the primary active material 216 may be doped and undoped during discharging and charging of the
battery, respectively. According to an exemplary embodiment, the primary active material 216 is lithium cobalt oxide (LiCoO.sub.2). According to another exemplary embodiment, the positive active material is of the form LiCo.sub.xNi.sub.(1-x)O.sub.2,
where x is between approximately 0.05 and 0.8. According to another exemplary embodiment, the primary active material is of the form LiAl.sub.xCo.sub.yNi.sub.(1-x-y)O.sub.2, where x is between approximately 0.05 and 0.3 and y is between approximately
0.1 and 0.3. According to other exemplary embodiments, the primary active material may include LiMn.sub.2O.sub.4.
According to various other exemplary embodiments, the primary active material may include a material such as a material of the form Li.sub.1-xMO.sub.2 where M is a metal (e.g., LiCoO.sub.2, LiNiO.sub.2, and LiMnO.sub.2), a material of the form
Li.sub.1-w(M'.sub.xM''.sub.y)O.sub.2 where M' and M'' are different metals (e.g., Li(Ni.sub.xMn.sub.y)O.sub.2, Li(Ni.sub.1/2Mn.sub.1/2)O.sub.2, Li(Cr.sub.xMn.sub.1-x)O.sub.2, Li(Al.sub.xMn.sub.1-x)O.sub.2, Li(Co.sub.xM.sub.1-x)O.sub.2 where M is a metal,
Li(Co.sub.xNi.sub.1-x)O.sub.2, and Li(Co.sub.xFe.sub.1-x)O.sub.2)), a material of the form Li.sub.1-w(Mn.sub.xNi.sub.yCo.sub.z)O.sub.2 (e.g., LiCo.sub.xMn.sub.yNi(.sub.1-x-y)O.sub.2, Li(Mn.sub.1/3Ni.sub.1/3Co.sub.1/3)O.sub.2,
Li(Mn.sub.1/3Ni.sub.1/3Co.sub.1/3-xMg.sub.x)O.sub.2, Li(Mn.sub.0.4Ni.sub.0.4Co.sub.0.2)O.sub.2, and Li(Mn.sub.0.1Ni.sub.0.1Co.sub.0.8)O.sub.2), a material of the form Li.sub.1-w(Mn.sub.xNi.sub.xCo.sub.1-2x)O.sub.2, a material of the form
Li.sub.1-w(Mn.sub.xNi.sub.yCo.sub.zAl.sub.w)O.sub.2 a material of the form Li.sub.1-w(Ni.sub.xCo.sub.yAl.sub.z)O.sub.2 (e.g., Li(Ni.sub.0.8Co.sub.0.15Al.sub.0.05)O.sub.2), a material of the form Li.sub.1-w(Ni.sub.xCo.sub.yM.sub.z)O.sub.2 where M is a
metal, a material of the form Li.sub.1-w(Ni.sub.xMn.sub.yM.sub.z)O.sub.2 where M is a metal, a material of the form Li(Ni.sub.x-yMn.sub.yCr.sub.2-x)O.sub.4, LiMn.sub.2O.sub.4, a material of the form LiM'M''.sub.2O.sub.4 where M' and M'' are different
metals (e.g., LiMn.sub.2-y-z Ni.sub.y, Li.sub.zO.sub.4, LiMn.sub.1.5 Ni.sub.0.5O.sub.4, LiNiCuO.sub.4, LiMn.sub.1-xAl.sub.xO.sub.4, LiNi.sub.0.5Ti.sub.0.5O.sub.4, and Li.sub.1.05Al.sub.0.1Mn.sub.1.85O.sub.4-zF.sub.z), Li.sub.2MnO.sub.3, a material of the
form Li.sub.xV.sub.yO.sub.z (e.g., LiV.sub.3O.sub.8, LiV.sub.2O.sub.5, and LiV.sub.6O.sub.13), a material of the form LiMPO.sub.4 where M is a metal or LiM.sub.x'M''.sub.1-xPO.sub.4 where M' and M'' are different metals (e.g., LiFePO.sub.4,
LiFe.sub.xM.sub.1-xPO.sub.4 where M is a metal, LiVOPO.sub.4, and Li.sub.3V.sub.2(PO.sub.4).sub.3, LiMPO.sub.4x where M is a metal such as iron or vanadium and X is a halogen such as fluorine, and combinations thereof.
The secondary active material 218 is a material that is selected to have relatively significant cyclable charge and discharge capacity (i.e., cyclable capacity) below the corrosion potential of the material used for a negative current collector
222 provided as part of the negative electrode 220 (and/or any other material to which the negative current collector is electrically attached or in electrical communication with, for example, a case or housing for the battery) and above the
decomposition potential of the primary active material 216. For example, according to an exemplary embodiment in which the negative current collector 222 comprises copper, for which the corrosion potential is approximately 3.5 volts, the secondary
active material 218 includes significant charge and discharge capacity below 3.5 volts.
The secondary active material 218 may or may not contain lithium. According to an exemplary embodiment in which the secondary active material does not include lithium, the secondary active material is V.sub.6O.sub.13. According to another
exemplary embodiment in which the secondary active material includes lithium, the secondary active material is LiMn.sub.2O.sub.4. According to various other exemplary embodiments, the secondary active material may be selected from the following
materials and combinations thereof: V.sub.2O.sub.5, V.sub.6O.sub.13, LiMn.sub.2O.sub.4 (spinel), LiM.sub.xMn.sub.(2-x)O.sub.4 (spinel) where M is metal (including Li) and where x is between approximately 0.05 and 0.4, Li.sub.4Ti.sub.5O.sub.12,
Li.sub.xVO.sub.2 (where x is between approximately 0 and 1), V.sub.3O.sub.8, MoO.sub.3, TiS.sub.2, WO.sub.2, MoO.sub.2, and RuO.sub.2.
According to an exemplary embodiment, electrochemically active or cyclable lithium may be added as finely divided or powdered lithium. Such powdered lithium may include a passive coating (e.g., a thin layer or film of lithium carbonate) provided
thereon to reduce the reactivity of the powdered lithium with air and moisture. Such material may be mixed with the secondary active material prior to application of the secondary active material to fabrication of the cells or may be added as another
separate active material layer.
The lithium added to the secondary active material 218 of the positive electrode 210 has significant charge/discharge capacity that lies below the corrosion potential of the negative current collector and/or any battery components to which it is
electrically connected (e.g., the case) and above the decomposition potential of the positive electrode active material. The lithium becomes significantly doped at a potential below the corrosion potential for the negative current collector 222. In so
doing, this material lowers the final potential of the positive electrode in the discharge state, so that the zero voltage crossing potential remains below the corrosion potential of the negative current collector and the battery case. The secondary
active material may be capable of releasing the lithium when the battery is charged.
It should be noted that while a variety of materials have been described above as being useful for secondary active material 218, a variety of additional materials may be utilized in addition to or in place of such materials. For example, the
secondary active material may comprise an oxide material such as one or more of Li.sub.xMoO.sub.3 (0&lt;x.ltoreq.2), Li.sub.xMoO.sub.2 (0&lt;x.ltoreq.1), Li.sub.xMo.sub.2O.sub.4 (0&lt;x.ltoreq.2), Li.sub.xMnO.sub.2 (0&lt;x.ltoreq.1),
Li.sub.xMn.sub.2O.sub.4 (0&lt;x.ltoreq.2), Li.sub.xV.sub.2O.sub.5 (0&lt;x.ltoreq.2.5), Li.sub.xV.sub.3O.sub.8 (0&lt;x.ltoreq.3.5), Li.sub.xV.sub.6O.sub.13 (0&lt;x.ltoreq.6 for Li.sub.xVO.sub.2.19 and 0&lt;x.ltoreq.3.6 for Li.sub.xVO.sub.2.17),
Li.sub.xVO.sub.2 (0&lt;x.ltoreq.1), Li.sub.xWO.sub.3 (0&lt;x.ltoreq.1), Li.sub.xWO.sub.2 (0&lt;x.ltoreq.1), Li.sub.xTiO.sub.2 (anatase) (0&lt;x.ltoreq.1), Li.sub.xTi.sub.2O.sub.4 (0&lt;x.ltoreq.2), Li.sub.xRuO.sub.2 (0&lt;x.ltoreq.1),
Li.sub.xFe.sub.2O.sub.3 (0&lt;x.ltoreq.2), Li.sub.xFe.sub.3O.sub.4 (0&lt;x.ltoreq.2), Li.sub.xCr.sub.2O (0&lt;x.ltoreq.3), Li.sub.xCr (0&lt;x.ltoreq.3.8), and Li.sub.xNi.sub.yCO.sub.1-yO.sub.2 (0&lt;x.ltoreq.1, 0.90&lt;y.ltoreq.1.00), where x is selected
such that these materials have little or no lithium that becomes undoped below the corrosion potential of the negative current collector during the first charge of the battery.
According to another exemplary embodiment, the secondary active material may comprise a sulfide material such as one or more of Li.sub.xV.sub.2S.sub.5 (0&lt;x.ltoreq.4.8), Li.sub.xTaS.sub.2 (0&lt;x.ltoreq.1), Li.sub.xFeS (0&lt;x.ltoreq.1),
Li.sub.xFeS.sub.2 (0&lt;x.ltoreq.1), Li.sub.xNbS.sub.3 (0&lt;x.ltoreq.2.4), Li.sub.xMoS.sub.3 (0&lt;x.ltoreq.3), Li.sub.xMoS.sub.2 (0&lt;x.ltoreq.1), Li.sub.xTiS.sub.2 (0&lt;x.ltoreq.1), Li.sub.xZrS.sub.2 (0&lt;x.ltoreq.1),
Li.sub.xFe.sub.0.25V.sub.0.75S.sub.2 (0&lt;x.ltoreq.1), Li.sub.xCr.sub.0.75V.sub.0.25S.sub.2 (0&lt;x.ltoreq.0.65), and Li.sub.xCr.sub.0.5V.sub.0.5S.sub.2 (0&lt;x.ltoreq.1), where x is selected such that these materials have little or no lithium that
becomes undoped below corrosion potential of the negative current collector during the first charge of the battery.
According to another exemplary embodiment, the secondary active material may comprise a selenide material such as one or more of Li.sub.xNbSe.sub.3 (0&lt;x.ltoreq.3), Li.sub.xVSe.sub.2 (0&lt;x.ltoreq.1). Various other materials may also be used,
for example, Li.sub.xNiPS.sub.3 (0&lt;x.ltoreq.1.5) and Li.sub.xFePS.sub.3 (0&lt;x.ltoreq.1.5), where x is selected such that these materials have little or no lithium that becomes undoped below corrosion potential of the negative current collector
during the first charge of the battery.
According to an exemplary embodiment, the thickness of the layer of active material 214 is between approximately 0.1 .mu.m and 3 mm. According to another exemplary embodiment, the thickness of the layer of active material 214 is between
approximately 25 .mu.m and 300 .mu.m. According to a particular exemplary embodiment, the thickness of the layer of active material 214 is approximately 75 .mu.m. In embodiments in which the primary active material 216 and the secondary active material
218 are provided as separate layers of active material, the thickness of the primary active material 216 is between approximately 25 .mu.m and 300 .mu.m (and approximately 75 .mu.m according to a particular exemplary embodiment), while the thickness of
the secondary active material 218 is between approximately 5 .mu.m and 60 .mu.m (and approximately 10 .mu.m according to a particular exemplary embodiment). The amount of the secondary active material 218 to be added is determined by the electrochemical
equivalents (i.e., capacity) of lithium that can be cycled from that material. According to an exemplary embodiment, the amount is as small as practical, because this minimizes the amount to which the battery's average operating voltage (and therefore
energy density) is reduced. According to another exemplary embodiment, the amount is at a minimum equal to the difference between the irreversible capacity of the negative electrode active material and that of the positive active material.
The negative current collector 222 included as part of the negative electrode 220 is made of a conductive material such as a metal. According to an exemplary embodiment, the current collector 222 is copper or a copper alloy. According to
another exemplary embodiment, the current collector 222 is titanium or a titanium alloy. According to another exemplary embodiment, the current collector 222 is nickel or a nickel alloy. According to another exemplary embodiment in which the negative
active material 224 is not carbon, the current collector 222 is aluminum or an aluminum alloy. It should also be noted that while the negative current collector 222 has been illustrated and described as being a thin foil material, the positive current
collector may have any of a variety of other configurations according to various exemplary embodiments. For example, the positive current collector may be a grid such as a mesh grid, an expanded metal grid, a photochemically etched grid, or the like.
According to an exemplary embodiment, the thickness of the current collector 222 is between approximately 100 nm and 100 .mu.m. According to another exemplary embodiment, the thickness of the current collector 222 is between approximately 5
.mu.m and 25 .mu.m. According to a particular exemplary embodiment, the thickness of the current collector 222 is approximately 10 .mu.m.
The negative current collector 222 has a negative active material 224 provided thereon. While FIG. 3 shows that the active material 224 is provided on only one side of the current collector 222, it should be understood that a layer of active
material similar or identical to that shown may be provided or coated on both sides of the current collector 222.
According to exemplary embodiment, the negative active material 224 is a carbonaceous material (e.g., carbon such as graphite). According to exemplary embodiment, the negative active material 224 is a lithium titanate material such as
Li.sub.4Ti.sub.5O.sub.12. Other lithium titanate materials which may be suitable for use as the negative active material may include one or more of include the following lithium titanate spinel materials: H.sub.xLi.sub.y-xTiO.sub.xO.sub.4,
H.sub.xLi.sub.y-xTiO.sub.xO.sub.4, Li.sub.4M.sub.xTi.sub.5-xO.sub.12, Li.sub.xTi.sub.yO.sub.4, Li.sub.xTi.sub.yO.sub.4, Li.sub.4[Ti.sub.1.67Li.sub.0.33-yM.sub.y]O.sub.4, Li.sub.2TiO.sub.3, Li.sub.4Ti.sub.4.75V.sub.0.25O.sub.12,
Li.sub.4Ti.sub.4.75Fe.sub.0.25O.sub.11.88, and Li.sub.4Ti.sub.4.5Mn.sub.0.5O.sub.12, and LiM'M''XO.sub.4 (where M' is a metal such as nickel, cobalt, iron, manganese, vanadium, copper, chromium, molybdenum, niobium, or combinations thereof, M'' is an
optional three valent non-transition metal, and X is zirconium, titanium, or a combination of these two). Note that such lithium titanate spinel materials may be used in any state of lithiation (e.g., Li.sub.4-xTi.sub.5O.sub.12, where
0.ltoreq.x.ltoreq.3).
One advantage of using a lithium titanate material instead of a carbonaceous material is that it is believed that the use of a lithium titanate material allows for charging and discharging of the battery at higher rates than is capable using
carbonaceous materials. Lithium titanate materials are also believed to offer superior cycle life because they are so called "zero-strain" materials. Zero strain materials have crystal lattices which do not experience shrinkage or contraction with
lithium doping/de-doping, making them free from strain-related degradation mechanisms. According to other exemplary embodiments, the negative active material 224 may be carbon, Li.sub.xAl, Li.sub.xSn, Li.sub.xSi, Li.sub.xSnO, metal nanoparticle
composites (e.g., including Li.sub.xAl, Li.sub.xSn, Li.sub.xSi, or Li.sub.xSnO), or carbon-coated lithium titanate.
Another advantageous feature of using a lithium titanate material is that it is believed that when used in a negative electrode of a lithium-ion battery, such materials will cycle lithium at a potential plateau of about 1.5 V versus a lithium
reference electrode. This is substantially higher than graphitic carbon, which is traditionally used in lithium ion batteries, and cycles lithium down to about 0.1 V in the fully charged state. As a result, the battery using lithium titanate is
believed to be less likely to result in plating of lithium (which occurs at 0 V versus a lithium reference) while being charged. Lithium plating is a well-known phenomenon that can lead to loss in performance of lithium ion batteries. Being free from
the risk of lithium plating, cells with lithium titanate negative electrodes may also be charged at rates that exceed those with carbon negative electrodes. For example, a common upper limit for the rate of charge in lithium ion batteries is about 1 C
(meaning that the battery can be fully charged from the discharged state in one hour). Conversely, it has been reported in literature that lithium titanate may be charged at rates up to 10 C (i.e., attaining full charge in 1/10 hour, or six minutes).
Being able to recharge a battery more quickly substantially increases the functionality of devices that employ such a battery. A further advantage of the higher potential of the lithium titanate material is that it avoids decomposition of organic
solvents (such as propylene carbonate) commonly used in lithium ion batteries. In so doing, it may reduce negative consequences such as formation of gas, cell swelling, reduction of reversible battery capacity, and buildup of resistive films which
reduce battery power.
A binder material may also be utilized in conjunction with the layer of active material 224. For example, according to an exemplary embodiment, the layer of active material may include a conductive additive such as carbon black and a binder such
as polyvinylidine fluoride (PVDF) or an elastomeric polymer.
According to various exemplary embodiments, the thickness of the active material 224 is between approximately 0.1 .mu.m and 3 mm. According to other exemplary embodiments, the thickness of the active material 224 may be between approximately 25
.mu.m and 300 .mu.m. According to another exemplary embodiment, the thickness of the active material 224 may be between approximately 20 .mu.m and 90 .mu.m, and according to a particular exemplary embodiment, may be approximately 75 .mu.m.
As shown in FIG. 3, a mass or quantity of electrochemically active lithium (shown as a piece of lithium in the form of a lithium patch or member 240) is shown as being coupled or attached to (e.g., in electrical contact with) the negative current
collector 222. Such a configuration corresponds to a situation in which the secondary active material 228 is provided without including electrochemically active lithium (e.g., the secondary active material 228 does not include lithium as it is coated on
the positive current collector). One such exemplary embodiment involves the use of V.sub.6O.sub.13 for the secondary active material. It should also be noted that electrochemically cyclable lithium may be added by adding lithium-containing compounds
such as a lithium intermetallic compound such as a lithium-aluminum compound, a lithium-tin compound, a lithium-silicon compound, or any other similar compound that irreversibly donates lithium at a potential below that of the corrosion potential of the
negative current collector (and any material to which it is electrically connected).
The electrochemically active lithium may be provided in other locations in the negative electrode 220 and/or may have a different size or shape than that shown schematically in FIG. 3. For example, the electrochemically active lithium may be
provided as a disc or as a rectangular piece of material coupled to the negative current collector. While the electrochemically active lithium is shown as being provided on a single side of the current collector 222 in FIG. 3 (e.g., as a lithium patch),
separate lithium patches may be provided on opposite sides of the current collector 222. Further, multiple lithium patches may be provided on one or more of the sides of the current collector 222. In another example, the lithium may be provided
elsewhere within the battery and connected (e.g., by a wire) to the current collector 222.
According to another exemplary embodiment, the electrochemically active or cyclable lithium may be added as finely divided or powdered lithium. Such powdered lithium may include a passive coating (e.g., a thin layer or film of lithium carbonate)
provided thereon to reduce the reactivity of the powdered lithium with air and moisture. Such material may be mixed with the negative electrode active material prior to application of the negative electrode active material to fabrication of the cells or
may be added as another separate active material layer. According to an exemplary embodiment, the finely divided or powdered lithium particles have a diameter of between approximately 1 .mu.m and 100 .mu.m, and according to a particular embodiment,
between approximately 5 .mu.m and 30 .mu.m.
One advantage of providing electrochemically active lithium at the negative electrode (e.g., in the form of one or more lithium patches) is that the secondary active material 228 may be partially or completely lithiated by the lithium to
compensate for the irreversible loss of capacity which occurs upon the first charging of the battery 200. For example, when the battery cell is filled with electrolyte, lithium from the lithium patch 240 is oxidized and inserted into the negative active
material (i.e., the lithium in the electrochemically active lithium is effectively "shorted" to the negative active material).
The electrochemically active lithium may also provide a number of additional advantages. For example, it may act to maintain the potential of the negative current collector below its corrosion potential prior to initial charging ("formation") of
the battery. The electrochemically active lithium may also aid in the formation of the solid-electrolyte interface ("SEI") at the negative electrode. Further, the electrochemically active lithium may provide the "formation" of the active material on
the negative electrode without a corresponding reduction in battery capacity as would occur when the source of lithium for formation is the active material from the positive electrode.
The amount of electrochemically active lithium is selected such the amount of electrochemical equivalents provided by the electrochemically active lithium at minimum corresponds to the irreversible capacity of the negative electrode active
material and at maximum corresponds to the sum of the irreversible capacity of the negative electrode active material and the capacity of the secondary active material 228. In this manner, the electrochemically active lithium at least compensates for
the irreversible loss of capacity which occurs on initial charging of the battery 200 and most preferably corresponds to the sum of the irreversible capacity of the negative electrode active material and the capacity of the secondary active material 228.
According to an exemplary embodiment in which a lithium patch 240 is utilized, the size the lithium patch 240 is between approximately 1.4 cm.times.1.4 cm.times.0.11 cm, which corresponds to approximately 0.013 grams (e.g., approximately 50 mAh). The specific size of the lithium patch may vary according to other exemplary embodiments (e.g., approximately 5-25 percent of the capacity of either the negative or positive electrode).
FIG. 5 is a graph 300 illustrating the theoretical charging and discharging behavior for a lithium-ion battery constructed in accordance with an exemplary embodiment such as that shown and described with regard to FIG. 3. Curve 310 represents
the electrode potential versus a lithium reference electrode for a positive electrode (e.g., positive electrode 210) that includes an aluminum current collector having a LiCoO.sub.2 primary active material and a secondary active material provided
thereon.
The secondary active material is selected to provide significant charging/discharging capacity below the corrosion potential (shown as dashed line 322) of the negative current collector and above the decomposition potential (shown as dashed line
312) of the LiCoO.sub.2 primary active material. According to an exemplary embodiment, the secondary active material is V.sub.6O.sub.13 or LiMn.sub.2O.sub.4. According to various other exemplary embodiments, the secondary active material may be
selected from the following materials and combinations thereof: V.sub.2O.sub.5, LiMn.sub.2O.sub.4, V.sub.6O.sub.13, LiM.sub.xMn.sub.(2-x)O.sub.4 (spinel) where M is metal (including Li), Li.sub.4Ti.sub.5O.sub.12, Li.sub.xVO.sub.2, V.sub.3O.sub.8,
MoO.sub.3, TiS.sub.2, WO.sub.2, MoO.sub.2, and RuO.sub.2.
Curve 320 represents the electrode potential versus a lithium reference electrode for a negative electrode that includes a copper current collector having a carbonaceous active material (i.e., carbon) and a lithium patch provided thereon. The
difference between curves 310 and 320 is representative of the overall cell voltage of the battery.
It should be noted that the theoretical charging and discharge behavior for the negative electrode is believed to be qualitatively similar to that shown in FIG. 5 for a copper current collector having a Li.sub.4Ti.sub.5O.sub.12 active material
provided thereon (as opposed to a carbon active material), with the relatively flat portion of the curve 320 being shifted upward to a level of approximately 1.57 volts (in contrast to the approximately 0.1 volts for the carbon active material).
Upon initial charging, the battery experiences an irreversible loss of capacity due to the formation of a passive layer on the negative electrode, which may be referred to as a solid-electrolyte interface ("SEI"). The irreversible loss of
capacity is shown as a ledge or shelf 324 in curve 320. The lithium patch is provided so as to compensate for the irreversible loss of capacity and to provide lithium to the second active material in the event of discharge to a voltage approaching zero. For example, as shown in FIG. 5, the relative capacity provided by the lithium patch is shown by arrow 328.
As shown in FIG. 5, the initial state of the cell, after it is filled with electrolyte and allowed to equilibrate, is indicated by dashed line XXX. The potential of the positive electrode, as shown by curve 310, is approximately 3 volts (shown
as point 311). The potential of the negative electrode, as shown by curve 320, is approximately 0.1 volts (shown as point YYY). When the cell is charged, the potentials of the positive and negative electrodes progress to the right along curves 310 and
320, respectively. When the cell is discharged, the potentials of the positive and negative electrode potentials progress toward the left.
The charging/discharging behavior of the primary and secondary active materials (e.g., primary active material 216 and secondary active material 218) provided on the positive current collector are shown in FIG. 5 as two portions 314, 316 of curve
310. Portion 314 of curve 310 represents the charging/discharging behavior of the positive electrode due to the doping and undoping of the primary active material (i.e., LiCoO.sub.2), while portion 316 of curve 310 represents the charging/discharging
behavior of the positive electrode due to the doping and undoping of the secondary active material (i.e., V.sub.6O.sub.13, LiMn.sub.2O.sub.4, etc.).
Upon discharging the battery to a point approaching zero volts, the negative electrode potential follows a path designated by line 326. However, because the secondary active material is chosen to have significant charging/discharging capacity
below the corrosion potential of the negative current collector and above the decomposition potential of the LiCoO.sub.2 primary active material, the zero voltage crossing potential (shown as point 330) is below the corrosion potential of the negative
current collector and above the decomposition potential of the LiCoO.sub.2 primary active material, thus avoiding corrosion of the negative current collector (and potentially of the battery case) and any associated loss of battery charging capacity.
It is intended that a lithium-ion battery such as that described herein may be fully discharged while the materials for both electrodes, including their corresponding current collectors, are stable (e.g., corrosion of the current collectors
and/or the decomposition of active material may be avoided, etc.). One potential advantageous feature of such an arrangement is that the occurrence of reduced device functionality (i.e., the need to recharge more frequently) and corrosion of the current
collectors and battery case (with the incumbent possibility of leaking potentially corrosive and toxic battery contents) may be reduced or avoided. Another advantageous feature of such an arrangement is that the battery may be repeatedly cycled (i.e.,
charged and discharged) to near-zero-voltage conditions without significant decline in battery performance.
Various advantageous features may be obtained by utilizing batteries such as those shown and described herein. For example, use of such batteries may eliminate the need to utilize circuitry to disconnect batteries approaching near-zero voltage
conditions. By not utilizing circuitry for this function, volume and cost reductions may be obtained.
According to an exemplary embodiment, lithium-ion batteries such as those described above may be used in conjunction with medical devices such as medical devices that may be implanted in the human body (referred to as "implantable medical
devices" or "IMD's").
FIG. 6 illustrates a schematic view of a system 400 (e.g., an implantable medical device) implanted within a body or torso 432 of a patient 430. The system 400 includes a device 410 in the form of an implantable medical device that for purposes
of illustration is shown as a defibrillator configured to provide a therapeutic high voltage (e.g., 700 volt) treatment for the patient 430.
The device 410 includes a container or housing 414 that is hermetically sealed and biologically inert according to an exemplary embodiment. The container may be made of a conductive material. One or more leads 416 electrically connect the
device 410 and to the patient's heart 420 via a vein 422. Electrodes 417 are provided to sense cardiac activity and/or provide an electrical potential to the heart 420. At least a portion of the leads 416 (e.g., an end portion of the leads shown as
exposed electrodes 417) may be provided adjacent or in contact with one or more of a ventricle and an atrium of the heart 420.
The device 410 includes a battery 440 provided therein to provide power for the device 410. According to another exemplary embodiment, the battery 440 may be provided external to the device or external to the patient 430 (e.g., to allow for
removal and replacement and/or charging of the battery). The size and capacity of the battery 440 may be chosen based on a number of factors, including the amount of charge required for a given patient's physical or medical characteristics, the size or
configuration of the device, and any of a variety of other factors. According to an exemplary embodiment, the battery is a 5 mAh battery. According to another exemplary embodiment, the battery is a 300 mAh battery. According to various other exemplary
embodiments, the battery may have a capacity of between approximately 10 and 1000 mAh.
According to other exemplary embodiments, more than one battery may be provided to power the device 410. In such exemplary embodiments, the batteries may have the same capacity or one or more of the batteries may have a higher or lower capacity
than the other battery or batteries. For example, according to an exemplary embodiment, one of the batteries may have a capacity of approximately 500 mAh while another of the batteries may have a capacity of approximately 75 mAh.
According to another exemplary embodiment shown in FIG. 7, an implantable neurological stimulation device 500 (an implantable neuro stimulator or INS) may include a battery 502 such as those described above with respect to the various exemplary
embodiments. Examples of some neuro stimulation products and related components are shown and described in a brochure titled "Implantable Neurostimulation Systems" available from Medtronic, Inc.
An INS generates one or more electrical stimulation signals that are used to influence the human nervous system or organs. Electrical contacts carried on the distal end of a lead are placed at the desired stimulation site such as the spine or
brain and the proximal end of the lead is connected to the INS. The INS is then surgically implanted into an individual such as into a subcutaneous pocket in the abdomen, pectoral region, or upper buttocks area. A clinician programs the INS with a
therapy using a programmer. The therapy configures parameters of the stimulation signal for the specific patient's therapy. An INS can be used to treat conditions such as pain, incontinence, movement disorders such as epilepsy and Parkinson's disease,
and sleep apnea. Additional therapies appear promising to treat a variety of physiological, psychological, and emotional conditions. Before an INS is implanted to deliver a therapy, an external screener that replicates some or all of the INS functions
is typically connected to the patient to evaluate the efficacy of the proposed therapy.
The INS 500 includes a lead extension 522 and a stimulation lead 524. The stimulation lead 524 is one or more insulated electrical conductors with a connector 532 on the proximal end and electrical contacts (not shown) on the distal end. Some
stimulation leads are designed to be inserted into a patient percutaneously, such as the Model 3487A Pisces-Quad.RTM. lead available from Medtronic, Inc. of Minneapolis Minn., and stimulation some leads are designed to be surgically implanted, such as
the Model 3998 Specify.RTM. lead also available from Medtronic.
Although the lead connector 532 can be connected directly to the INS 500 (e.g., at a point 536), typically the lead connector 532 is connected to a lead extension 522. The lead extension 522, such as a Model 7495 available from Medtronic, is
then connected to the INS 500.
Implantation of an INS 520 typically begins with implantation of at least one stimulation lead 524, usually while the patient is under a local anesthetic. The stimulation lead 524 can either be percutaneously or surgically implanted. Once the
stimulation lead 524 has been implanted and positioned, the stimulation lead's 524 distal end is typically anchored into position to minimize movement of the stimulation lead 524 after implantation. The stimulation lead's 524 proximal end can be
configured to connect to a lead extension 522.
The INS 500 is programmed with a therapy and the therapy is often modified to optimize the therapy for the patient (i.e., the INS may be programmed with a plurality of programs or therapies such that an appropriate therapy may be administered in
a given situation). In the event that the battery 502 requires recharging, an external lead (not shown) may be used to electrically couple the battery to a charging device or apparatus.
A physician programmer and a patient programmer (not shown) may also be provided to allow a physician or a patient to control the administration of various therapies. A physician programmer, also known as a console programmer, uses telemetry to
communicate with the implanted INS 500, so a clinician can program and manage a patient's therapy stored in the INS 500, troubleshoot the patient's INS 500 system, and/or collect data. An example of a physician programmer is a Model 7432 Console
Programmer available from Medtronic. A patient programmer also uses telemetry to communicate with the INS 500, so the patient can manage some aspects of her therapy as defined by the clinician. An example of a patient programmer is a Model 7434
Itrel.RTM. 3 EZ Patient Programmer available from Medtronic.
While the medical devices described herein (e.g., systems 400 and 500) are shown and described as a defibrillator and a neurological stimulation device, it should be appreciated that other types of implantable medical devices may be utilized
according to other exemplary embodiments, such as pacemakers, cardioverters, cardiac contractility modulators, drug administering devices, diagnostic recorders, cochlear implants, and the like for alleviating the adverse effects of various health
ailments. According to still other embodiments, non-implantable medical devices or other types of devices may utilize batteries as are shown and described in this disclosure.
It is also contemplated that the medical devices described herein may be charged or recharged when the medical device is implanted within a patient. That is, according to an exemplary embodiment, there is no need to disconnect or remove the
medical device from the patient in order to charge or recharge the medical device. For example, transcutaneous energy transfer (TET) may be used, in which magnetic induction is used to deliver energy from outside the body to the implanted battery,
without the need to make direct physical contact to the implanted battery, and without the need for any portion of the implant to protrude from the patient's skin. According to another exemplary embodiment, a connector may be provided external to the
patient's body that may be electrically coupled to a charging device in order to charge or recharge the battery. According to other exemplary embodiments, medical devices may be provided that may require removal or detachment from the patient in order
to charge or recharge the battery.
It is also important to note that the construction and arrangement of the lithium-ion battery as shown and described with respect to the various exemplary embodiments is illustrative only. Although only a few embodiments of the present
inventions have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of
the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited in the claims. Accordingly, all such
modifications are intended to be included within the scope of the present invention as defined in the appended claims. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the
preferred and other exemplary embodiments without departing from the scope of the present invention as expressed in the appended claims.
* * * * *